Title explains most of it. Try exploring a jungle without quitting the game in a newly generated world. And then try again but quitting and reloading the world after spawning and waiting for some of it to generate, and then exploring. In the first case everything will be fine, but in the latter case you will see some artifacts.
P.S. This is not related to the failing to generate decorations on random quarter chunks bug.
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Does MC-125007 describe the experienced behavior? It seems very similar, if not identical.

Nope. I described the difference.

Tell that to MC-240280.
You did not describe any actual difference, the ps at the end only simply states "it's different" with no reasoning to back it up. That is why I had ultimately missed the note.
Just saying it's different without elaborating the difference doesn't make it any different.

Thank you for your report!
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